Cloth winder having cutter and pressure bar

ABSTRACT

In a cloth winder for sheet material, the cloth is pushed down or engaged from above by a pressure bar or the like at two zones, one forward and one rearward in the direction of progression of the sheet material with respect to the location of the cutter. In one embodiment the cutter has a pusher abutment which engages the fabric opposite a foot on the pressure bar so that the pressure bar initially raises as the cutter raises, and then moves rapidly away from the cutter to permit the new roll to start.

ilnited States Patent [72] Inventor Walter E. Aulen Woodstown, NJ. [21] Appl. No. 854,986 [22] Filed Sept. 3, 1969 [45] Patented Oct. 19, 1971 [73] Assignee Eddystone Machinery Company Chester, Pa.

[54] CLOTH WINDER HAVING CUTTER AND PRESSURE BAR 1 1 Claims, 12 Drawing Figs.

[52] US. Cl 242/56 R, 83/455, 242/66 [51] Int. Cl..' B65h 19/20 [50] Field of Search 242/56, 56.6, 65, 66, 64, 65 A; 83/262, 455, 390

[ 56] References Cited UNITED STATES PATENTS 2,599,942 6/1952 Roen 242/56 3,009,376 11/1961 Rose etal....,..,..... 242/56X 3,061,221 10/1962 Aulen 242/66 3,167,268 l/1965 Birch et al. 242/56 3,385,149 5/1968 Johnson I. 83/455 X 3,386,678 6/1968 Malone l 242/56 Primary Examiner-Stanley N. Gilreath Assistant Examiner-Werner l-I. Schroeder Att0rneyJacks0n, Jackson and Chovanes ABSTRACT: In a cloth winder for sheet material, the cloth is pushed down or engaged from above by a pressure bar or the like at two zones, one forward and one rearward in the direction of progression of the sheet material with respect to the location of the cutter. In one embodiment the cutter has a pusher abutment which engages the fabric opposite a foot on the pressure bar so that the pressure bar initially raises as the cutter raises, and then moves rapidly away from the cutter to permit the new roll to start.

PATENTEDUET 19 197i SHEET 10F 4 INVENTOR Wafferfi. flnfzn ATTORNEYS PATENTEDHET 19 I911 3,614,010 SHEET 2 OF 4 BY 9 Q Mk mm C/ ATTORNEYS SHEET a BF 4 PATENTEDUET 19 l97| NVENTOR Wa/ er ATTORNEYS CLOTH WINDEIR HAVING CUTTER AND PRESSURE BAR DISCLOSURE OF INVENTION The present invention relates to winders for sheet material, commonly called cloth winders, and to processes of winding.

A purpose of the invention is to increase the speed of cutting sheet material on a winder.

A further purpose is to obtain a cleaner cut of sheet material as it is wound.

A further purpose is to increase the effectiveness of cutters.

A further purpose is to more effectively cut high-loft sheet material such as open felt on a cloth winder.

A further purpose is to assist in cutting tensionless material which is being wound on the cloth winder.

A further purpose is to protect against creating wrinkles at the starting end of a new roll due to the action of cutting.

A further purpose is to yieldingly engage the sheet material out of contact with the cutter at zones adjacent the cutting zone both forward and rearward of the cutting zone at the time of the cut, thus obtaining an improved cutting action but not a shearing action.

A further purpose is to contact the sheet material from above by a pressure bar which is pushed rapidly upward out of the way after the cut has been made.

A further purpose is to withdraw the pressure bar ahead of the upward motion of the cutter.

A further purpose is to compress the cloth at the time of cutting to facilitate cutting.

Further purposes appear in the specification and in the claims. In the drawings l have chosen to illustrate one only of the numerous embodiments in which the invention may appear, selecting the form shown for the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

FIG. I is a partially diagrammatic fragmentary section of a three-drum winder embodying the principles of the invention, the section being taken on the line 1-1 of FIG. 2.

FIG. 2 is a fragmentary partially diagrammatic plan section of the three-drum winder of the invention, the section being taken on the line 2-2 of FIG. 1.

FIG. 3 is a fragmentary detail side elevation showing the pressure bar and its cylinder and the knife, the pressure bar being in engagement with the top of the sheet material and the knife rising to make the cut.

FIG. 4 is an electric circuit diagram for the mechanism operating the pressure bar and the knife. FIG. 5 is a pneumatic circuit diagram for the mechanism operating the knife.

FIGS. 6 to are fragmentary diagrammatic vertical sections showing steps in operation of the pressure bar and the knife.

FIG. 6 shows both the pressure bar and the knife retracted.

FIG. 7 shows the pressure bar lowered to engage the upper surface of the sheet material, but the knife retracted.

FIG. 8 shows the knife advancing and engaging the sheet material to make the cut.

In FIG. 9 the pressure bar has begun to retract.

In FIG. 10 both the pressure bar and the cutter have retracted.

FIG. 11 is a fragmentary view corresponding to FIG. 8, showing a variation.

FIG. 12 is a fragmentary view corresponding to FIG. 3 showing a further variation. Describing in illustration but not in limitation and referring to the drawings:

The principles of the invention are applicable generally to winding machines for sheet material, whether of the two-drum type, as shown for example in my U.S. Pat. No. 3,061,221, granted Oct. 30, 1962, for Winding Machine, or of the threeclrum type as shown in my U.S. Pat. No. 3,045,940 granted July 24, 1962 for Three-drum Winder.

I illustrate a three-drum winder of the type referred to in the above patent, which is incorporated by reference and made a part hereof as showing additional features present in a winder of this sort.

Considerable difficulty has been encountered under some conditions of winding on a winding machine, in making a completely clean cut. Where the cut has not been clean, there is a tendency to create wrinkles or unevenness in the roll which starts as the cut end is would on the next shell. Among the conditions which have led to difficulty in making a clean cut, is winding at higher speed, in which the tendency to create irregularities by cutting may be greater.

Another difficult cutting job on a winder is the cutting of high-loft materials, such as open felt. It is also difiicult to cut materials which are arriving at the winder in a tensionless condition.

Some dense materials such as carpets are very difficult to cut without using the present invention.

The present invention therefore is concerned with improving the quality of the cut edge as to straightness, freedom from wrinkles, freedom from loose threads or lint, and absence of longitudinal tears, and make it possible to cut at higher speeds. Another feature of the invention is that high-loft material, material which is arriving in tensionless condition, and dense material can be cut effectively by the present invention.

In the prior art as shown in Lyth U.S. Pat. 1,979,334 granted Nov. 6, 1934 for Machine for Winding Material of Ribbonlike Form Into Rolls, the cloth at the time of cutting is engaged from above by a bar in close proximity to the knife and rearward of the knife in the direction of progression of the sheet material. No pressure is applied forward of the knife. The pressure bar is advanced and withdrawn entirely independently of the knife. It is not clear as to whether this contemplates that the pressure bar is to cooperate with the knife in causing shearing of the cloth.

I-Iuck U.S. Pat. 3,279,716 granted Oct. 18, 1966 for Continuous Web Winding Rollstand, shows a cutter working against an anvil in a cloth winder.

In accordance with the present invention, the sheet material is contacted from above both forward and rearward of the knife in the direction of progression and entirely out of contact with the cutting edge of the knife. No shearing takes place and shearing is not desired, as this causes danger of grabbing the sheet material and producing uneven rolling, wrinkling or irregular tearing.

In the preferred embodiment, the knife carries with it a clamping member which engages the fabric on one side, the other side at that point being engaged by a foot on the pressure bar, and the knife pushes the pressure bar up very slightly and then the pressure bar rapidly retracts. The pressure bar rises more rapidly than the knife so that the pressure bar is out of the way in advance of the time that the forward end of the new roll must be wound on the new shell.

First considering the winder in detail, a frame 20 has uprights 21 and has three spaced horizontal parallel shafts 22, 23 and 24, each of which is driven in the same direction by suitable driving means. The shaft 22 is supported in the frame by suitable bearings (not shown) and has keyed thereon an entering drum 25. The shaft 23 is journaled in the frame on bearings 26 (FIG. 2) and has keyed thereon a middle drum 27. The shaft 24 is journaled on the frame in bearings 28 and has keyed thereon a letoff drum 30. A driving interconnection between the drums is suggested by sprocket and chain mechanism 31 shown in FIG. 2.

In the preferred embodiment letoff drum 30 and middle drum 27 are suitably made larger than entering drum 25, and letoff drum 30 is placed forward and substantially below the middle drum 27, the line of centers suitably being at an angle between 10 and 30 and preferably about 20 to the horizontal as shown.

The winding machine has above the entering drum 25 chutes 32 downwardly directed toward the entering drum, and provided with pivoted latches 33 for releasing pivot ends 34 of a new shell 35 on which a new roll can be wound. Generally horizontal rails 36 extend across to guide the pivots so that the new shell can wind on the entering drum.

Uprights of the frame above the entering drum have vertical guideways 37 in which upper jaws 38 carry spaced, antifriction bearing rollers which pivotally engage the pivot ends 34 of the new shell 35. The upper jaws 38 connect to piston and piston rod combinations 40 operating in double-acting pneumatic cylinders 41 secured to the uprights, and capable of applying downward pressure on the new shell, or retracting the upper jaws to release the new shell and roll for transfer as later explained.

Between the entering and the middle drum and below them, there are at the sides of the machine generally vertical or slightly inclined guideways 43 which guide a gate or frame 44 which has at its upper end suitable knife or cutters 45 and threading fingers 46 as well known in the art. The knife 45 may if desired be of the character shown in my U.S. Pat. No. 3,045,940 or it may be circular cutters as shown in my U.S. Pat. No. 3,061,221 or of any other suitable type. The cutting edges of the knife will desirably be inclined toward the direction from which the sheet material arrives at the point of cut.

The knife is raised and lowered by double-acting pneumatic cylinders 47 having piston and piston rod combinations 48 connected to the frame or gate.

The introduction of a new shell 35 and the cutting of the sheet material 49 will be accomplished in any suitable way, as by hand or otherwise, as well known in the art. Thus while the sheet material is winding on the letoff and middle drums, the new shell 35 is placed under the upper jaws 38 above the sheet material, the new shell is pressed downward against the material by the jaws, and turns with the sheet material against the entering drum until cutting takes place. At the time of cutting, the gate or frame 44 rises and the knife 45 cuts the sheet materials, and the threading fingers 46 as well known carry the cut end around the new shell 35. The roll 49' then winds as in conventional practice on the entering drum until it has increased to a size shown at 49' at the left in FIG. 1, and is ready for transfer. Transfer to the letoff and middle drums can be made in any suitable manner as well known in the art, either manually or preferably by transfer arms 50 pivoted on shaft 51 supported on the frame, the transfer arms 50 extending down to a position behind the pivot ends 34 of the shell. The transfer arms may be manipulated by a suitable means as well known.

As the roll 49 being wound moves to a position above the middle drum 27, the roll pivot ends 34 come in contact with letdown arms 57 which form the subject matter of my U.S. Pat. No. 3,06l,221 above referred to, and which are pivoted on shaft 23 and operated pneumatically. Double-acting pneumatic cylinder 58 pivoted on the frame at 60 has a piston and rod combination 61 which is pivotally connected at 62 with lever 63 keyed on shaft 64 journaled on the frame at 65. The shaft 64 also has keyed thereon at opposite ends levers 66 which are pivotally connected at 67 to adjustable links 68 which pivotally connect at 70 intermediate the ends of letdown arms 57.

After the letdown arms operate, and the transfer is completed, the roll 49 being wound, is resting on and turning with the letoff drum 30 and the middle drum 27. In this position pivot jaws 71 sliding in guideways 72 in the frame, engage the pivot ends 34 of the roll 49. The pivot jaws 71 have bearing rollers at each end to journal the pivot ends 34 of the shell and the pivot jaws 71 resist any tendency of the roll 49' to oscillate between the drums, wind asken or jump off the drums. Alternatively the pivot jaws 71 may be below the pivot ends 34, so as to reduce the pressure on the sheet material from the weight of the roll in winding.

Each of the pivot jaws 71 is urged in the proper direction by a piston and rod combination 73 operating in a double-acting pneumatic cylinder 74 which is pivoted on the frame at 75.

When the cloth roll 49' is wound to the size suitable for doffing, it has of course pushed the pivot jaws 71 up along the guideways 72 against or with the action of the cylinders 74. At this point cutting is accomplished. In order to doff and load the cloth roll on a truck, hoister the like, bearings 71 are raised, and a doffing roll 76 is actuated which is placed below the roll of cloth, is pivoted on an axis 77 parallel with the axis of the roll of cloth, on bearing supports 78 which are mounted on piston and rod combinations 80 operating in pneumatic cylinders 81 mounted on the frame.

In accordance with the present invention, a pressure bar extends across above the stretch of sheet material 49 which extends between the entering drum 25 and the middle drum 27. The pressure bar 100 (FIG. 3) is supported at its opposite ends on piston and rod combinations 102 operating in double-acting pneumatic cylinders 103 mounted on an upper support 104 on the frame. The pressure bar 100 has an upper position remote from the sheet material and a lower position in which it is just in engagement with the top of the sheet material or adjacent the top of the sheet material. Its line of motion toward and away from the sheet material is parallel to the line of motion of the gate or frame in raising the knife 45, it being remembered that the knife is preferably slightly inclined toward the direction from which the sheet material arrives. The pressure bar 100 of the preferred form has at its rearward end a foot 105 which engages the sheet material in a zone out of contact with the cutting surface of the knife disposed rearward of the knife in the direction of progression of the sheet material, and also has a foot 106 which engages the sheet material out of contact with the cutting surface of the knife in a zone spaced from the knife forward of the knife in the direction of progression. Thus the pressure bar without engaging the cutting surface of the knife in the manner of shearing, straddles the location of the cut in providing pressure on the sheet material from above at the time of cutting.

Mounted with the knife is a clamping member 107 desirably located on the side of the knife forward in the direction of progression of the sheet material and when the knife moves upward the clamping member 107 contacts the sheet material on the side opposite to the foot 106 and pushes the pusher bar 100 upward out of the way. Optionally as shown in FIG. 11, a clamping member 107 can be located on the side of the knife from which the cloth comes, in position to cooperate with the foot 105 on the pressure bar at that side.

It is desired, however, as soon as the cut is complete to remove the pressure bar and this is conveniently accomplished by applying fluid pressure to the cylinders 103 in a direction to raise the pressure bar at a more rapid rate than the upward advance of the knife.

Referring to the electric circuit shown in FIG. 4, power leads 110 and 111 have connected across them with suitable switching a solenoid valve 112 which operates the pneumatic cylinders which raise and lower the knife, and a solenoid valve 113 which operates the pneumatic cylinders which lower and raise the pressure bar. Each of the solenoid valves 112 and 113 is pneumatically a four-way valve which in one position connects the cylinder to air pressure at one end and to exhaust at the other end, and in the other position connects the cylinder to air pressure at the other end and to exhaust at the one end. Each of the solenoid valves is of the type which remains in its thrown position until energized by the opposite solenoid to shift it.

One circuit branch 114 connected across the power lines 110 and 111 has in it a double-pole switch 115 of the instantaneous contact type which when closed connects across contacts 116 to energize solenoid 117 in solenoid valve 112 so as to connect knife cylinders 47 to fluid pressure in the direction to raise the knife, connecting the other ends of knife cylinders to exhaust. The other pole of switch 115 closes contacts 118 so as to energize solenoid 120 of solenoid valve 113 so as to lower the pressure bar. The pneumatic connections to pressure bar cylinders 103 which tend to lower the pressure bar are unobstructed, but the pneumatic connections to raise the cutters have restrictions 121 in them as shown in Flg. 5, so that while 115 closes both poles at the same time, the pressure bar moves into engagement with the top of the sheet material a short time before the cutter touches the material.

Switch 115 is spring biased toward opening and as soon as it has been closed and is released, it immediately opens.

As the knife moves upward it clamps the sheet material momentarily against the pressure barjcuts the sheet material, closes limit switch 122 in circuit branch 123 and energizes solenoid 124 in solenoid valve 113 so as to move the fluid connections in the direction to cause the pressure bar to raise rapidly.

This raising motion is more rapid than the upward motion of the knife because of the restrictions 121 and therefore the pressure bar retracts upwardly ahead of the cutter. As the cutter still moves upward, it closes limit switch 125 in circuit branch 126 to energize solenoid 127 of solenoid valve 112 so as to move the cutter downward into its retracted position.

Limit switches 122 and 125 are of the instantaneous closing and then opening type so that they cease to be energized immediately after they have been closed.

The electrical and pneumatic connections, except as set forth above, may be as shown in FIGS. 3 and 4 of Aulen U.S. Pat. No. 3,045,940 above referred to.

In operation, once a roll winding on the entering drum is large enough, it is transferred to the letoff drum and middle drum 27 by transfer arms 50 cooperating with letdown arms 57. The roll then winds on the middle and letoff drums, under holddown pressure if desired from the jaws 71, or under upward pressure from these jaws to reduce the compactness where required.

A stretch of sheet material 49 progresses across the space between the entering drum and the middle drum above the knife or cutter.

When it is desired to accomplish cutting according to the invention with the cutter and pressure bar in the position of FIG. 6, switch 115 is momentarily closed by the operator, and this energizes solenoid valve 112 in the direction to cause the knife to move upward and energizes solenoid valve 113 in the direction to cause the pressure bar to move downward. Due to the retardation imposed in the pneumatic system of the knife, the pressure bar completes its downward motion before the knife contacts the sheet material, as shown in FIG. 7.

The clamping of the material between the pressure bar and the knife on one or both sides of the knife aids in obtaining a cleaner and more rapid cut. As the knife moves upward it momentarily pushed the pressure bar upward causing clamping of the sheet material as about to take place in FIG. 8.

A suitable abutment (not shown) on the knife closes limit switch 122, FIG. 4, shifting pressure bar solenoid valve 113 in the direction to retract the pressure bar and the pressure bar moves rapidly upward as shown in FIG. 9 ahead of the cutter. Shortly afterward, limit switch 125, FIG. 4, is contacted by the knife abutment and energizes solenoid valve 112 so as to retract the knife to its inactive position, FIG. 10.

Since the pressure bar never contacts the cutting edges of the knife, there is no shearing or grabbing during the cut which could cause wrinkles or uneven rolls.

At this stage, the roller of cloth on the letoff and middle drums is turning without connection with the cloth being received by the winder and being wound on the new shell. Doffing is accomplished by releasing pivot jaws 71 as described in my patent above referred to, retracting letdown arms 57 and raising doffing roll 76 so that it ejects the fully wound cloth roll onto a suitable track, hoist or the like. 17

In operation, once a roll 49' winding on the entering drum 25 is large enough, it is transferred to the letoff drum 30 and middle drum 27 by transfer arms 50 cooperating with letdown arms 57. The roll then winds on the middle and letoff drums, holddown pressure being applied by jaws 71, or relief of pres sure being applied.

A stretch of sheet material is progressing across the space between the entering drum and the middle drum above the knife.

If the cloth is very open in construction, there will be an advantage in providing clamping members 107 and 107' both forward and behind the cutter in the direction of cloth progression, so as to clamp the cloth to the feet 106 and of the pressure bar on both sides at the time of cut, as shown in FIG. 11.

If the cloth is very likely to be injured by the pressure bar, a series of downwardly directed air nozzles 105' and 106' can replace the feet 105 and 106 to exert downward pressure on the cloth.

In view of my invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such insofar as they fall within the reasonably spirit and scope if my claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent Is:

1. In a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so that the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction to progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and means for raising the pressure bar, the knife having a clamping member which engages the sheet material and the pressure bar having a foot which engages the sheet material opposite the clamping member, whereby the sheet material is clamped at the moment if cutting.

2. A winding machine of claim 1, in which the knife has clamping members which engage the sheet material momentarily at the time of cutting and in which the pressure bar has a foot engaging the sheet material opposite to each clamping member.

3. In a winding machine, for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of the progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife and means for raising the pressure bar, in which the means for raising the knife acts slowly and the means for lowering the pressure bar acts rapidly.

4. In a winding machines, for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letofidrum and thus draw a stretch of material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so that the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, in which the means for raising the pressure bar withdraws it faster than the rise of the knife after the cut.

5. In a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means lowering the pressure bar to a position adjacent to the sheet material at a point spaced in the direction of the progression of the sheet material from the location of the cut, a clamping member on the knife, a foot on the pressure bar opposite the clamping member, and means for retracting the pressure bar.

6. in a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letofi" drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind it at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, means for raising the knife to cut off the sheet material acting relatively slowly at the later part of the upward motion of the knife, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the sheet material at a point spaced in the direction of the progression of the sheet material from the location of the cut, a clamping member on the knife a foot on the pressure bar opposite the clamping member, and means for retracting the pressure bar, acting more rapidly than the means for raising the knife.

7. A winding machine for sheet material, having a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, a clamping member on the knife which engages the sheet material momentarily at the time of cut on at least one side ofthe knife and remote from the knife, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent the sheet materiaLa foot on the pressure bar engaging the sheet material opposite the clamping member and means for retracting the knife.

8. A winding machine of claim 7 in combination with clamping members on both sides of the knife and remote from the knife and out of engagement with the knife for engaging the sheet material.

9. A process of winding and cutting sheet material, using an entering drum and a letoff drum, which comprises winding the sheet material on a shell against the entering drum to form a roll, transferring the roll to wind at least in part on the letoff drum, thus drawing a stretch of sheet material against the space between the drums, raising a knife from below to engage the stretch of sheet material and cut it and pushing downward against the sheet material at the time of cutting on both sides of the knife, but free from contact with the cutting surfaces of the knife and withdrawing the pressure as the knife rises.

10. A process of winding and cutting sheet material, using a horizontal entering drum and a parallel horizontal letoffdrum, which comprises winding a roll of sheet material on a shell against the entering drum, transferring the roll to wind at least in part on the letotf drum, thus drawing a stretch of sheet material across a space between the drums, raising a knife from below to engage the stretch of sheet material and cut it, pushing upward on the sheet material at a zone remote from the knife as the knife cuts, and pushing downward on the sheet material opposing the zone of upward pushing as the knife cuts.

11. A process of claim 10, which comprises pushing downward on the sheet material opposing zones of upward pushing on both sides of the knife as the knife cuts. 

1. In a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so that the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction to progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and Means for raising the pressure bar, the knife having a clamping member which engages the sheet material and the pressure bar having a foot which engages the sheet material opposite the clamping member, whereby the sheet material is clamped at the moment if cutting.
 2. A winding machine of claim 1, in which the knife has clamping members which engage the sheet material momentarily at the time of cutting and in which the pressure bar has a foot engaging the sheet material opposite to each clamping member.
 3. In a winding machine, for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of the progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife and means for raising the pressure bar, in which the means for raising the knife acts slowly and the means for lowering the pressure bar acts rapidly.
 4. In a winding machines, for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife extending beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the upper surface of the sheet material prior to the cut, so that the pressure bar will make contact with the sheet material during the cut along a zone spaced forward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, and also along a zone spaced rearward with respect to the direction of progression of the sheet material from the knife and out of contact with the cutting surface of the knife, in which the means for raising the pressure bar withdraws it faster than the rise of the knife after the cut.
 5. In a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheeT material, means lowering the pressure bar to a position adjacent to the sheet material at a point spaced in the direction of the progression of the sheet material from the location of the cut, a clamping member on the knife, a foot on the pressure bar opposite the clamping member, and means for retracting the pressure bar.
 6. In a winding machine for sheet material, a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind it at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, means for raising the knife to cut off the sheet material acting relatively slowly at the later part of the upward motion of the knife, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent to the sheet material at a point spaced in the direction of the progression of the sheet material from the location of the cut, a clamping member on the knife a foot on the pressure bar opposite the clamping member, and means for retracting the pressure bar, acting more rapidly than the means for raising the knife.
 7. A winding machine for sheet material, having a horizontal entering drum, a spaced-parallel horizontal letoff drum, means for turning the drums in the same direction, pivot means for a shell adapted to wind on the entering drum to form a roll, means for transferring the roll from the entering drum to wind at least partially on the letoff drum and thus draw a stretch of sheet material across a space toward the letoff drum with respect to the entering drum, pivot means for the shell when winding on the letoff drum, a knife beneath the stretch of sheet material, a clamping member on the knife which engages the sheet material momentarily at the time of cut on at least one side of the knife and remote from the knife, means for raising the knife to cut the sheet material, and means for lowering the knife, in combination with a pressure bar above the stretch of sheet material, means for lowering the pressure bar to a position adjacent the sheet material, a foot on the pressure bar engaging the sheet material opposite the clamping member and means for retracting the knife.
 8. A winding machine of claim 7 in combination with clamping members on both sides of the knife and remote from the knife and out of engagement with the knife for engaging the sheet material.
 9. A process of winding and cutting sheet material, using an entering drum and a letoff drum, which comprises winding the sheet material on a shell against the entering drum to form a roll, transferring the roll to wind at least in part on the letoff drum, thus drawing a stretch of sheet material against the space between the drums, raising a knife from below to engage the stretch of sheet material and cut it and pushing downward against the sheet material at the time of cutting on both sides of the knife, but free from contact with the cutting surfaces of the knife and withdrawing the pressure as the knife rises.
 10. A process of winding and cutting sheet material, using a horizontal entering drum and a parallel horizontal letoff drum, which comprises winding a roll of sheet material on a shell against the entering drum, transferring the roll to wind at least in part on the letoff drum, thus drawing a stretch of sheet material across a space between the drums, raising a knife from below to engage the stretch of sheet material and cut it, pushing upward on the sheet material at a zone remote from the knife as the knife cuts, and pushing downward on the sheet material opposing the zone of upward pushing as the knife cuts.
 11. A process of claim 10, which comprises pushing downward on the sheet material opposing zones of upward pushing on both sides of the knife as the knife cuts. 